Effects of stuttering on fundamental frequency

The purpose of this study was to systematically investigate quantitative fundamental frequency measures prior to moments of stuttering, and relate these measures to the severity and type of stuttering. A repeated readings adaptation procedure was employed to acquire samples of the stuttered and identical fluent speech of stutterers. Thirty-six utterance pairs were classified by type of stuttering (absence of phonation, prolongation, or repetition). A fundamental frequency meter was sampled by a microprocessor computer system at a rate of 256 samples/1.024 sec. Four temporal periods (each 256 msec) preceding the stuttering block were compared with the same periods in a fluently produced sample of similar speech. The analyses revealed differences relative to mean fundamental frequency, variation around the mean fundamental frequency, and the number of voiced data points contained within each temporal segment. The results of this study confirm the existence of acoustic changes in the vocal production of stutterers prior to overt blocks. These changes relate to the type of block that follows. Individual variations that emphasize the need for analyses of within subject differences were found.     

Effects of subgrouping in stuttering research

The most frequently utilized research design in stuttering research compares stutterers to nonstutterers, with the assumption that stutterers represent a homogeneous group. The present study examines the effects of subgrouping stuttering subjects. Sample populations were randomly selected from a pool of stuttering children, successively increasing the stringency of selection criteria for group membership. The groups were contrasted across five dependent variables. The results indicated that the performance differences between the groups increased as the selection criteria became more stringent. The findings were interpreted as supporting the need to more closely examine the individual differences of stutterers, deviating from the traditional research paradigm.     

Effects of simulated stuttering on listener recall

In an investigation of the effects of simulated stuttering on listener recall, a presentation was varied on two factors: degree of stuttering (mild or severe) and information value of stuttered words (low or high). A control presentation featuring non-stuttered speech also was prepared. Five groups of 16 subjects were randomly assigned to, and participated in, one of the five listening conditions. Then they completed a 20-item recall test. A one-way analysis of variance revealed sognificant differences among the five conditions. Two-way analysis of variance disclosed no main effects. However, a significant interaction showed that recall was lowest in the severe stuttering-high information condition. The results are discussed in terms of attention to critical information.     

A case of persistent neurogenic stuttering following a missile wound

Observational criteria that have been proposed to distinguish developmental from neurogenic stuttering are critically reviewed. It is concluded that both conditions may closely resemble each other. As an example, a case of neurogenic stuttering following a missile would is reported.     

A case of adult onset of stuttering

A 36-yr-old adult male was treated for stuttering after a “sudden onset” of disfluency according to the client, 3 yr before. The treatment method and results are described and the “awareness” feature of stuttering onset is discussed.     

A case report on the use of flooding in stuttering therapy

The last several years have seen the development and use of anxiety-reduction procedures in stuttering therapy. Among these types of methods, systematic desensitization and reciprocal inhibition have been employed almost exclusively. Emotional de-conditioning by means of flooding or implosive techniques has been attempted far less often. This article presents a case report on the utilization of the flooding tactic. Results are offered and discussed relative to the question of whether the elimination of anxiety is a realistic goal in therapy. The suggestion is offered that what many stutterers may really need to develop is the ability to generate fluency-enhancing behaviors in spite of the presence of heightened emotionality.     

His mother-tongue: from stuttering to separation, a case history

This paper delineates the transference and countertransference experiences in the analysis of a patient whose presenting symptom and main concern was his stutter. I suggest that oral-sadistic rather than anal-sadistic hostile elements may be identified in this patient's particular stutter. I focus on its significance in terms of object relationship: my patient's struggle to 'get born', to emerge as a separate other. I argue that early symbiotic fusion needs in conflict with the need to separate produce his stutter. Speech and language are seen as the vehicle for separation and the stutter as a flight from separateness back to an illusion of fusion with mother.     

A case of late-onset or acquired stuttering in adult life

A case of acquired stuttering in adulthood is presented which may be psychogenic in onset with a neurologic base.     

Voluntary stuttering suppresses true stuttering: a window on the speech perception-production link

In accord with a proposed innate link between speech perception and production (e.g., motor theory), this study provides compelling evidence for the inhibition of stuttering events in people who stutter prior to the initiation of the intended speech act, via both the perception and the production of speech gestures. Stuttering frequency during reading was reduced in 10 adults who stutter by approximately 40% in three of four experimental conditions: (1) following passive audiovisual presentation (i.e., viewing and hearing) of another person producing pseudostuttering (stutter-like syllabic repetitions) and following active shadowing of both (2) pseudostuttered and (3) fluent speech. Stuttering was not inhibited during reading following passive audiovisual presentation of fluent speech. Syllabic repetitions can inhibit stuttering both when produced and when perceived, and we suggest that these elementary stuttering forms may serve as compensatory speech gestures for releasing involuntary stuttering blocks by engaging mirror neuronal systems that are predisposed for fluent gestural imitation.     

Effects of delayed auditory feedback on acquired stuttering following head injury

This study examined the effects of Delayed Auditory Feedback (DAF) with three cases of acquired stuttering following head injury. To determine the effects of DAF on stuttering behavior a multiple baseline design across three speaking tasks was employed. All subjects reduced stuttering with application of DAF. Stuttering behavior on untreated tasks continuing in baseline was not affected by DAF. When treatment was applied to the untreated tasks, stuttering events decreased for all three subjects. Results indicate DAF has potential as a treatment procedure with cases of acquired stuttering in a way similar to cases of developmental stuttering.     

Acquired stuttering following right frontal and bilateral pontine lesion: a case study

We report neurological information and experimental data regarding acquired neurogenic stuttering in a 57-year-old male following ischemic lesion to the orbital surface of the right frontal lobe and the pons. The experimental data consist of stuttering frequency measures under various conditions that are well known to enhance fluency in most individuals with developmental stuttering. Specifically, we report data for adaptation, unison reading, delayed auditory feedback (DAF), and frequency altered feedback (FAF). This work is the first published report of such a comprehensive examination of a variety of fluency-enhancing conditions in acquired stuttering. The patient read six 200-word texts under different conditions: Six solo readings (Text 1), five unison readings followed by five solo readings (Text 2), five readings with non-altered auditory feedback (Text 3), five readings with 50 ms delayed auditory feedback (Text 4), five readings with increased FAF (Text 5), and five readings with decreased FAF (Text 6). Results indicate that, unlike the typical situation for developmental stuttering, this individual with acquired neurogenic stuttering did not show increased fluency during an adaptation paradigm or under unison, DAF, and FAF conditions. We discuss possible implications of these findings and emphasize the need for further research on acquired neurogenic stuttering.     

Influence of stuttering therapy on clinicians'' disfluencies: Effects of client modeling

This study investigated whether student clinicians working with stutterers subsequently produce more disfluencies than student clinicians providing therapy to clients with other speech and language disorders. Seventeen graduate students working in a 6-wk summer camp setting were divided into two groups: eight who provided treatment for stutterers (group 1) and nine who provided therapy for clients with other communication disorders (group 2). All student clinicians were recorded during spontaneous speaking and oral reading tasks prior to camper arrival and following camper departure. An eight-category classification system was used to determine disfluency types. Findings revealed that Group 1 clinicians significantly decreased their total disfluencies between pre- and post-camp recordings on the spontaneous speaking task. Unexpectedly, this same group also substantially increased part-word repetitions and sound prolongations. The possibilities of incidental learning, reverse modeling, and overidentification with stuttering clients are discussed.     

Drawing with oblique coordinates: on a single case

We describe a patient with right hemisphere damage affected by mild left visuo-spatial neglect and constructional apraxia. During the rehabilitation, he failed to draw a draught-board using horizontal and vertical trajectories, but he performed it successfully using oblique trajectories. These observations suggested an impairment of vertical/horizontal spatial coordinates system. In copying tasks including figure elements in different orientations he drew more accurately components in oblique orientation, whereas failed to reproduce components in horizontal orientation. The patient performed visuospatial perceptual and perceptual-imaginative tasks successfully. From these findings, it is possible to suggest that the oblique coordinate system of reference operates independently of vertical and horizontal coordinate systems in building a complex figure and that, therefore, cardinal orientation do not constitute a reference norm to define oblique orientation, as previously suggested.     

Genetic studies of stuttering in a founder population

Genome-wide linkage and association analyses were conducted to identify genetic determinants of stuttering in a founder population in which 48 individuals affected with stuttering are connected in a single 232-person genealogy. A novel approach was devised to account for all necessary relationships to enable multipoint linkage analysis. Regions with nominal evidence for linkage were found on chromosomes 3 (P=0.013, 208.8 centiMorgans (cM)), 13 (P=0.012, 52.6 cM), and 15 (P=0.02, 100 cM). Regions with nominal evidence for association with stuttering that overlapped with a linkage signal are located on chromosomes 3 (P=0.0047, 195 cM), 9 (P=0.0067, 46.5 cM), and 13 (P=0.0055, 52.6 cM). We also conducted the first meta-analysis for stuttering using results from linkage studies in the Hutterites and The Illinois International Genetics of Stuttering Project and identified regions with nominal evidence for linkage on chromosomes 2 (P=0.013, 180-195 cM) and 5 (P=0.0051, 105-120 cM; P=0.015, 120-135 cM). None of the linkage signals detected in the Hutterite sample alone, or in the meta-analysis, meet genome-wide criteria for significance, although some of the stronger signals overlap linkage mapping signals previously reported for other speech and language disorders. EDUCATIONAL OBJECTIVES: After reading this article, the reader will be able to: (1) summarize information about the background of common disorders and methodology of genetic studies; (2) evaluate the role of genetics in stuttering; (3) discuss the value of using founder populations in genetic studies; (4) articulate the importance of combining several studies in a meta-analysis; (5) discuss the overlap of genetic signals identified in stuttering with other speech and language disorders.     

Effects of sex of listener and of stutterer on ratings of stuttering speakers

Attitudinal surveys relating to stutterers show conflicting evidence as to how stutterers are perceived. Studies have not addressed the question of possible sex differences as a determining variable in the rating of stuttering speakers. This study found a significant effect of the sex of the rater, with male subjects rating stuttering speakers less favorably on a number of personality dimensions than female raters.